Technical Field
This Patent Disclosure relates generally to electromechanical systems that generate back-emf, and more particularly to providing protection from back-emf for such systems.
Related Art
A Speaker is an electromechanical system that is capable of storing energy in reactive electrical components, as well as in mechanical components like moving masses and compressed springs.
The amplifier drives current to the speaker coil (and passive electrical components in the speaker). Mechanical energy stored in the speaker coil and other mechanical components is transformed back into a current that travels back to the amplifier.
The magnitude of the back-EMF current can be large compared to driven current. As a result, the total current at the amplifier output can trigger overcurrent protection in situations where only the driven current would not.
One approach for protecting against back-emf current is to overdesign the amplifier to handle worst case current. This solution disadvantageous particularly because the worst case current is sporadic and seldom (based on combinations of audio and speaker).
While this Background information references audio speaker systems, the Disclosure in this Patent Document is not limited to such applications, but is more generally directed to predictive back-emf protection for electromechanical systems.